1. Field of the Invention
This invention relates to an electronic control device for controlling the temperature of flowing liquid, for controlling the level of the liquid within a container and for maintaining the desired temperature within the container.
2. Information Disclosure Statement
Various types of devices have been used for controlling the temperature and level of a liquid within a container. In addition, liquid controlling devices have found use in industrial, commercial, residential and medical applications. One particular application for liquid controlling devices is the home use of water such as bathtubs, sinks, showers and the like.
Historically, many types of baths and bathtubs have been manufactured. The Romans were renowned for their ingenuity as to the provision of various types of baths. More recently, attention has turned to the manufacture of a bathtub that will not only enhance the ease with which an operator may take a bath or shower, but more particularly a need has existed in the art for controlling the temperature and flow functions of the water within the bath. In the past it has been customary for the person desiring a bath to close the drain plug manually and then turn the hot and cold water faucets to the required setting to fill the bath with the requisite level of water. When the water level has reached the required height, the faucets are closed and the bath is ready for use.
However, certain problems have been experienced in carrying out the various operations as outlined hereinbefore. First, with many elderly or infirm persons, bending over a bathtub to close the drain presents a serious problem. Second, when a bath is to be run and the hot water faucet is opened before the cold one, scalding can take place unless approximately the correct setting of the hot and cold water faucets is already known. Third, if the flow of water from the open faucet is relatively slow, there exists a temptation to become involved with another task while the bath is running and this often results in the bath overflowing or at least a waste of hot water if the faucets are not closed when the required water level is reached. Fourth, there is no provision in a conventional bathtub to maintain the water temperature at a desired level.
Referring to the prior art, U.S. Pat. No. 2,991,481 to Booke discloses an electronic control circuit for controlling the mixing of hot and cold water from a supply prior to flowing into a bathtub. Although this invention describes an overflow shut-off device for stopping the flow of water into the bathtub when the water level reaches an overflow, no disclosure is made of a selective level control. Furthermore, no disclosure is made of means for maintaining the preselected temperature of the water within the bathtub.
U.S. Pat. No. 4,042,984 to Butler, describes an automatic drain control and electronic circuit for controlling the quantity of water flowing into a bathtub. However, the quantity of water supplied is dependent on a clock controlled solenoid valve and not on the water level. Therefore, in the event of an increase in water pressure, the quantity of water supplied to the bathtub would exceed the required quantity and might result in an overflow.
U.S. Pat. No. 4,202,060 to Touze, discloses a bathtub having a sidewall access and a float controlled water level governing device.
U.S. Pat. No. 4,248,444 to Orszullok discloses a capacitive proximity switch for detecting the level of water within a bathtub. U.S. Pat. No. 4,080,985 to Eagle, describes the operation of a float which slides within a tube to control the level of water entering a bathtub. U.S. Pat. No. 2,991,482 to Brass, describes a side entry bathtub but does not disclose any control circuitry regarding temperature or water levels. Various other devices have been proposed for regulating the water level and temperature of washing machines and the like, but have not solved the major problems of the prior art.
Although the aforementioned patents solve many of the needs of the prior art by providing level controls and temperature controls, none of the prior art devices teach an electronic control device which will selectively control the temperature with which the liquid is delivered to a container, maintain the required temperature of liquid within the container and control the level to which the liquid within the container will rise. Therefore, it is a primary object of the present invention to provide an electronic device that overcomes the aforementioned inadequacies of the prior art devices and provides an improvement that significantly contributes to the electronic control not only of the temperature of liquid entering the container, but also the maintenance of the temperature of the liquid within the container regardless of the loss of heat to the surroundings.
Another object of the present invention is the provision of an electronic control device which automatically permits the liquid level to rise to a preselected level within the container and to maintain such level in the event that the volume of liquid is displaced by an object entering the container.
Another object of the present invention is the provision of an electronic control for a bathtub in which the opening or the closing of the bathtub door is controlled in accordance with a preselected switch.
Another object of the present invention is the provision of an electronic control for regulating the water level, drain and shower head functions by means of solid state circuitry.
A further object of the present invention is the provision of an electronic control for a bathtub having a side access which is particularly suitable for use by infirm or aged persons.
A still further object of the present invention is the provision of an electronic control device for a bathtub which affords a degree of control heretofore unknown in the art.
A further object of the present invention is the provision of a display circuit for displaying the temperature of a liquid within a container.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the present invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Although the invention is described with reference to a bathtub, it should be appreciated by those skilled in the art that the invention may find application in industrial, commercial and medical applications and the like.